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Trane 800-ton CVHE with adaptiview (AFD Drive)

Got a control cabinet with an AFD TR-200 in it, just installed and Trane can't figure out why they keep getting a "Phase Loss" alarm from it. CT's and PT's have all been checked for Polarity (unsure about phasing, which could be the problem), all wires are landed correctly. They have disabled "Momentary Phase Loss" and "Phase Reversal" still with no luck. Unsure if they have adjusted the metering of the CT's as it is factory set for the application. Also, unsure if they have checked for proper rotation of the compressor, as it is a new install. I would not think you would get a "Phase Loss" if the motor rotation was incorrect, but I am unsure of that. The starter module in the cabinet is receiving a constant 24V. Maybe they need to slightly decrease ramp up time for this phase loss to go away without harming the SCR's?

I do not know if 2T17 (PT) has to corrolate with 2T1 (CT) on the same phase as it is shown on the diagram, and 2T18 (PT) with 2T2, and 2T19 (PT) with 2T3?

if my book is current (and it may not be especially considering the application), there is a warning called 'Mains Phase Loss' which is a voltage issue, not an amperage issue. this could be due to a faulty PT or actual voltage unbalance. you may need to look into the programming too for trip points for this feature.

again, i may be all wet here for this application.

what is the full model number of the drive and what is the exact fault?

This is also uncharted territory for me. I've never seen a TR-200 running a chiller. Is Phase Loss coming from the TR-200 display or the Adaptiview display? I bet you've got a PT or CT that is marked incorrectly. There is a specific process for identifying which one is faulty that your Trane startup techs should be able to get in a piece of literature entitled "MPL Troubleshooting".

I do not know if 2T17 (PT) has to corrolate with 2T1 (CT) on the same phase as it is shown on the diagram, and 2T18 (PT) with 2T2, and 2T19 (PT) with 2T3?

CT and PT wiring must corrolate with the wiring diagram, so on the assumption the phase loss diagnostic is originating from the Adaptiview and not the drive (based on the fact that you mention MPL and Phase Reversal protection has been disabled - note disabling only desensitizes the protection) the primary question is the motor kicking from the starter or not - if yes you should be able to see if the CT's are registering any current even if out of scale if no it could be a starter or control/wiring/CT issue. You can ohm out the CT's but it is not readily easy to confirm the starter module is registering the input from the CT's.

The criteria for a Phase Loss Diagnostic is:

With phase reversal protection enabled the UC800 must see current on all 3 CTS > 20% RLA (must hold 20%, must trip 5% actual trip point 10%) within 0.7 seconds

With phase reversal protection disabled the trip time for a phase loss diagnostic trip time is increased to approx 3 seconds.

If it was a starter response or ramp time issue and the motor is kicking I would expect the disabling of the phase reversal protection would mostly overcome or improve the situation.

If a CT is faulty you would expect the time difference between 0.7 to approx 3 seconds to be noticable and sufficient time to determine if all three phase currents are displaying and if they are it could be a CT scaling issue or ramp setting in the drive.

So assuming you are not seeing any reaction from the starter the first check would be you are seeing a constant constant control power supply to J10-3 on the starter module - this control feed is fed from the chiller HP switch.

The starter module initiates a chiller start by momentarilary energizing terminal J8-1 to the pilot relay which must latch via it's auxillary from J10-1.

Trane should be able to dry run the start sequence using Tracer TU to confirm the starter control operation.
If this is all functioning correctly it most likely comes down to an issue with the drive requiring trouble shooting.

Hope this helps and I am not heading you in the wrong direction from assumptions

Screwit and jayguy - Trane had their big wig service guy come in today with the service supervisor and they got it running. They stated that they "didn't do anything, it just started working when they tried it". I find that really hard to believe. I think it was something so simple they didn't want to admit to it, but who knows. I think pride sometimes gets in the way of the truth with Trane, at least that's been my experience.

And yes, phase loss was coming from the adaptiview. Voltage on L1 and L2 was 489V and on L3 it was 490V

Screwit and jayguy - Trane had their big wig service guy come in today with the service supervisor and they got it running. They stated that they "didn't do anything, it just started working when they tried it". I find that really hard to believe. I think it was something so simple they didn't want to admit to it, but who knows. I think pride sometimes gets in the way of the truth with Trane, at least that's been my experience.

And yes, phase loss was coming from the adaptiview. Voltage on L1 and L2 was 489V and on L3 it was 490V

The drive is from Danfoss

Love jobs that just simply fix themselves - easy money.

I think you have it nailed as to the cause of the fault - sounds like a program setting or wiring error.